Astronics / EADS / Talon Instruments SR112 8 Channel RS485 Differential Stimulus / Response Module

The Astronics/EADS/Talon Instruments SR112 is an 8-channel RS485 differential stimulus/response module engineered for industrial data transmission and reception over RS485 networks. Differential signaling delivers enhanced noise immunity in automation, control, and data acquisition systems. The module integrates into VXI chassis environments as part of larger stimulus/response test systems, supporting reliable bidirectional communication with RS-485 standard compliance.

Technical Specifications

Channels: 8 differential RS485 stimulus/response channels

Standard: RS-485 compliant for balanced multipoint transmission

Data Rates: Up to 25 MHz; 50 MHz in multiplexed mode

Timing Rates: Up to 50 MHz

Channel Memory: Up to 128 Kbits per channel, expandable to 256 Kbits in multiplexed mode

Memory Architecture: Stimulus, Tristate, Record, Expect, and Mask

Input High Threshold: Typically 2.0 V

Input Low Threshold: Typically 0.8 V

Input Impedance: >10 kΩ

Output High Level: Typically >2.4 V

Output Low Level: Typically <0.4 V

Source Current: 50 mA

Sink Current: 50 mA

Output Impedance: 50 Ω

Short Circuit Protection: Standard on outputs

Key Features

Differential RS485 signaling for superior noise rejection

Stimulus generation and response capture on all 8 channels

Voltage support: TTL levels, RS485/422, and variable ±15 V or +5 V/−2 V options

Scalable memory per channel with multiplexed mode expansion

Operates within VXI chassis framework

Typical Applications

Industrial automation and control systems

Long-distance multipoint data acquisition

RS485 network stimulus/response testing

Noisy industrial environments requiring differential signaling

Compatibility & Integration The SR112 works with integration within VXI chassis housing. The SR192 Digital Test Module accommodates up to 12 I/O modules per chassis for 96 to 192 total channels. Multiple SR192 systems can be linked to reach 1152 channels within a single VXI chassis. Logic options include RS485/422, TTL, and ECL configurations.